Dry shaving device



Patente Feb. is. 193e DRY SHAVING DEVICE Harry Landsiedel, Wilton,Conn., assigner, by

mesne assignments, to General Shaver Corporation, Bridgeport,

Delaware Conn., a corporation of Application March 4, 1937, Serial No.128,936

4 Claims.

This invention relates to improvements in shaving devices oi' the typewhich do not necessitate the use of shaving preparations of any kind.

The general object of the invention is to pro- .5 vide an improved formof cutter head comprising an outer shear plate, and an inner cutter,movable transversely with respectl thereto, and involving moreparticularly improvements in the cutter bar portions of the outer shearplate.

The more detailed objects of the invention will be apparent from thefollowing description.

This invention resides substantially in the combination, construction,arrangement and relative location of parts, all as will be described inconnection with the attached drawing.

The subject matter of this application is re*- lated to that of mycopending application Serial No. 123,162, filed January 30,- 1937 forShaver.

In the accompanying drawing,

Figure 1 is a part of a side elevational view of the cutter head withmany parts broken away lto show other parts in cross section;

Fig. 2 is a vertical transverse sectional view through the cutter head;y Fig. 3 is an enlarged detail side elevational vviewof a portion of thecutter head.

IIn dry shaving devices of the type herein dis-l closed the outer shearplate, which is commonly slotted to provide a plurality of cutter bars,is -applied at its outer face to the surface of the skin, and the innercutter which operates in back of the shear plate against the rear faceof the cutter bars therein. The hairszto be clipped enter the slots andare cut off at the rear edges of the cutter bars of the outer shearplate. It is at once apparent, therefore. that the thickness of theouter shear plate at the cutter bars, in part, at

least, determines how close the hairs are cut oil? to the surface of theskin. The cutter bars are 4o therefore of necessity made extremely thinwith the result that they are physically weakened.

The central object of this invention is to provide an improvedconstruction at the cutter bars of the outer shear plate where portionsof the active lengths thereof are made much thinner without renderingthem impractical.

Referring to' the drawing at I is shown the upper end of the usualhandle casing which houses the motor for operating the device. As

shown, the upper end of the vcasing is grooved as indicated at 2 toreceive the cutter head assembly. 'I'he cutter head assembly is lockedin the groove by a set screw not shown, and posil tioned therein by apin 3 mounted in the casing so .as to engage a recess in the cutterhead.

The cutter head comprises an outer member t which may be made from asolid block of suitable steel, or formed up in other ways, as is knownin' the art, 'to provide a hollow upper section having a relativelythin, substantially semicircular wall 6. This wall is provided with aseries oftransverse slots 'I extending therethrough and outwardly awayfrom a central portion 8 which forms a continuous band extendinglongitudinally along the upper face of the wall 6. Aligned with y theslots 1, and' extending` further down vthe sides of the wall 6, are aseries of wider slots 9. These sets of aligned slots 'I and 9, onopposite sides of the wall 6, as is clear from Fig. 2, form the cutterbars I0 at the active portion which forms what is commonly termed theouter shear plate. At this point it is apparent thatthe wall 6 is, atthe portions under consideration, of substantially uniform thickness. Inorder to produce the fin-` ished shear plate it is now subjected to aseries of grinding operations to reduce the thickness of. the bars Illand the strip 8, leaving the raised ends as is clear in the figures. 1To accomplish this the ends of the bars I0 adjacent the strip 8 areground on iiat planes I I which lie at an angle of approximately 12degrees to the horizontal.

This would leave the stript! triangular in cross section but the top ispreferably ground off tothe form shown in Fig. 2 where it is more nearlyrectangular in cross section and substantially of uniform thickness.vThe bars I0 at their outer ends are again ground along hat planes I2which lie at an angle of approximately 24 degrees to the horizontal. Theresult is that the bars I0, viewedv from the side as they are in Fig. 2,take a form as clearly illustrated where it,comprises two parts eachthinnest intermediate the ends of the parts as indicated at I3 and ofincreasing cross section away from the center towards the ends of theparts. This provides a relatively strong cutter bar I0 which at no pointis much thinner than four or five one-thousandths of an inch, and which,at the thinnest point, may be made less than two one-thousandths o f aninch thick. The present commercial practice is to make the cutter barsof the order of four one-thousandths of an inch thick. Any attempts tomake a bar of uniform thickness any thinner than this, are met withpractical diiculty. However, by means of the construction heredisclosed, portions at least of the cutter bars, in the case illustratedthere are two such portions, may be made much thinner than this inshearing a vvery close shave. By reason of the fact that each bar isprovided with l two extremely thin portions, the device shaves veryrapidly, and since these portions lie so to speak in diierent planes,the outer shear plate does not have to be held against the skin asaccurately as is true with the usual fiat surface shaver. The slots 'lare provided with the wider portions l to permit easy entry of the hairthereinto by means of which they are guided to and into the narrow slots1 where they may be cut. In practice it is desirable to make the slot 'labout eight one-thousandths of an inch wide and the slots 9, fromfifteen to twenty-ve one-thousandths of an inch wide.

The inner cutter it is substantially circular in cross section and isprovided with a series of transverse slots I6 on the thinner Wall formedby its eccentric bore to form the inner continuous cutter bars l5. Aswill be seen from Fig. 2, the length of the cutter bars l5 is suflicientto bridge the expanse of the cutter bars lil. One end of the innercutter is slotted as indicated at I1 to cooperate with the head I8 ofthe pin mounted in the member 4 to insure rectilinear reciprocation ofthe inner cutter. The sides of the inner cutter near the ends of theslots I6 may be ground away as indicated at I9 to give relief and reducethe frictional resistance to movement of the inner cutter.

As is common in this art the inner cutter is engaged by an oscillatablelever 20 operated by the motor not shown. At 2l are indicated a pmr ofpins which are resiliently urged by springs not shown in a direction toforce the inner cutter against the rear faces of the cutters bars I0.

From the above description it will be apparent to those skilled in theart that some variation in the details of construction may be effectedwithout departure fromthe true scope of the invention. I do not,therefore, desire to be strictly limited to the disclosure as given forpurpose, of illustration, but rather to the appended claims.

What I seek to secure by United States Letters Patent is:

1. A dry shaving head comprising an outer shear plate slotted to form a.series of cutter bars, each of the slots being continuous and comprisingtwo portions of uniformly different width and an inner cutter mountedfor reciprocal movement across the rear faces of the cutter bars, saidcutter bars being curved on their rear faces and having a plurality offiat intersecting outer faces.

2. A shaving device as described comprising an outer shear plate havinga plurality of slots therein, the individual slots each having a wideand a narrow portion, and an inner cutter mounted for reciprocationtransversely of the rear faces of the cutter bars formed by said slots,said cutter bars increasing in thickness in both directions from twospaced points intermediate the ends thereof.

3. In a cutter head for a shaving implement an outer shear platecomprising a curved wall having a plurality of parallel slots to form aplurality of cutter bars, the outer faces of the cutter bars forming twoplanes each lying at an acute angle to a common plane, and said slotseach comprising two portions of uniform but different width.

4. A shaver head of the type described comprising an outer member havinga passage therethrough forming a wall, the rear surface of which is aportion of a cylinder, the smallest dimension transversely ofthe axis ofsaid passage being at least twice as great as `the radius of saidcylindrical portion, an inner reciprocable member mounted in saidpassage having a portion of its outer surface cylindrical and engagingthe cylindrical portion of the outer member, said inner member having apassage therethrough and being transversely slotted to form cutter bars,the outer member being provided with slots which intersect itscylindrical portion and arranged in two rows, the slots of therespective rows terminating short of each other to form a reinforcingbar extending at *right angles to the slots thereby forming two rows ofcutter bars, the outer faces of each row of cutter bars being cut awayon two flat planes, the corresponding planes of each pair converging andforming acute angles with planes at right angles to the radial planewhich includes their lines of convergence respectively.

HARRY LANDSIEDEL.

